1. Field of the Invention
After the slaughter of meat animals, various foreign materials, including blood, bone dust, hair, dirt, fecal matter, and contaminating microorganisms are generally adhered to the carcass surfaces. Certain microorganisms are capable of growing and causing spoilage at refrigeration temperatures and some may be pathogenic. Of course, carcasses must be substantially free of all such foreign material in order to exceed the minimum Governmental regulatory standards and to be acceptable for market. This invention relates to a system for effectively cleaning meat animal carcasses prior to refrigeration.
2. Description of the Prior Art
In the smaller slaughterhouse operations, it is conventional for carcasses to be washed with a stream of water emitted from a handheld nozzle. This technique is not particularly effective insofar as areas are sometimes missed and the single stream has a tendency to shift the foreign material from one area to another without actually removing it from the surface. Larger operations have incorporated washing units wherein the carcasses are passed through the spray emitted from a series of opposed stationary nozzles. Alternatively, in U.S. Pat. No. 3,674,211, F. H. Gage et al. shows a washer in which banks of spray nozzles are oscillated up and down as the carcasses pass through. These automated devices frequently fail to satisfactorily clean the carcasses and often require a manual spraying operation as a backup.
The effects of water volume, line pressure, angle of droplet impact, mean droplet size, total force of spray, and speed of travel through the spray on red meat have been previously reported by Anderson et al. [J. Food Sci. 40: 1232-1235 (1975)]. While this publication indicates that the proper selection of physical spray factors is critical to effective removal of microorganisms from a meat surface, a suitable apparatus for removing nearly 100% of all forms of contaminants from an irregularly shaped carcass surface has heretofore not been suggested.